California Reaches Major Housing Milestone–More than 100,000 ADUs Permitted Since 2017

Today we celebrate that California has permitted more than 100,000 ADUs across the state over the last seven years. The California Department of Housing and Community Development’s dashboard of Annual Progress Reports reflects this incredible milestone with data reported by California cities and counties.

We extend our congratulations and gratitude to each and every homeowner who built an ADU home and all of the professionals involved in designing, permitting and building them. We are incredibly proud of the role that our organization and our multi-sector coalition played in this success story. Casita Coalition’s founders collaborated with state legislators to co-author the state’s first strong ADU laws–AB 2299 and SB 1069 in 2016. Once the laws were implemented, ADU permits soared from 1,336 ADUs in 2016 to 5,154 in 2017, and they’ve continued to steadily climb since then, with nearly 25,000 ADUs permitted in 2022. 

While multigenerational living and homeowners adding living space to rent to community members to help make ends meet is not new, the permitted ADU as a distinctive housing type is a new phenomenon–and it now makes up almost 20% of all housing permitted statewide, and up to 30% and more in some cities.

Last year the Casita Coalition leveraged this success into AB 1033’s allowance for ADUs to be sold as condos, creating a new pipeline of affordable homes for purchase–a much-needed category for first-time homebuyers, downsizers and for the future of resilient housing. 

The journey to 100k 


Casita's founders observed the emergence of informal ADUs in their Bay Area neighborhoods, recognizing the potential for a grassroots housing revolution. Drawing inspiration from cities such as Portland, Vancouver, and Seattle, which had embarked on their ADU journey before California, they formalized the Casita Coalition with a dedicated board of directors. Beginning with strategic partnerships with housing nonprofits, legislators and academic researchers, Casita's founders gathered a diverse coalition (including many that had never been on the same side of an issue before,) united in the belief that homeowners, given the opportunity, would construct legal ADUs to take care of their families and house community members, and that these ADU homes could alleviate the housing shortage and address the affordability crisis.

Since 2017, we've worked diligently to dismantle zoning barriers through statewide legislation, liberating ADU development from burdensome constraints like owner-occupancy mandates, parking stipulations, and discretionary reviews. Our efforts have led to instituting 'by-right' allowances for ADUs on both single-family and multifamily properties. Additionally, we’ve committed to improving homeowner ADU access by enhancing financing options, and disseminating success stories from pioneering municipalities. Our coalition has stood firm against detrimental bills that threatened to stifle the ADU industry, uniting stakeholders from diverse backgrounds, including industry experts, planning officials, lenders, and researchers. 

Today, our efforts have expanded beyond ADUs to embrace other forms of middle housing. As we continue this journey, our commitment to removing barriers (at the local and systems level) and fostering collaboration remains unwavering.

ADUs have captured the attention of the nation

In California, accessory dwelling units have become the ‘little housing engine that can’, steadily ticking along adding new attainable housing options to neighborhoods despite high interest rates, pandemic shutdowns, state budget shortfalls and high construction costs. The majority of these homes are used for long term rentals at more affordable rents, built by a diverse range of homeowners. 

As California's success in fostering ADU-friendly zoning captures the attention of policymakers, a groundswell of change is gaining momentum nationwide. Daily headlines herald cities and states endeavoring to overhaul their zoning laws to embrace ADUs and middle housing forms, recognizing their urgent need amidst a mounting housing crisis. Despite each locality's unique landscape, the commonality of predominantly single-family zoned land (averaging 75% in most cities) underscores the shared imperative for reform.

Support the Casita Coalition in making possible the next 100k homes

As a relatively small organization with ambitious goals and big impact, we rely on the support of our extended network, which includes institutional gifts, philanthropic investments, sponsorships and partnerships, and membership dues to scale our impact. Learn more about the many ways you can help us co-create a future with attainable housing options.

As 2023 reports from more municipalities continue to upload to the data dashboard, this 100k milestone will keep growing. Make sure you’re signed up for our newsletter to stay updated!


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